The Fraunhofer Institute for Manufacturing Engineering and Automation IPA, in collaboration with its partners, is developing a bivalent furnace that allows for dynamic switching between gas and electricity. This innovation aims to address the high energy consumption and cost factors associated with melting and holding furnaces in the production of castings. By enabling flexible energy consumption, companies can optimize their production processes based on the most cost-efficient energy source available at any given time.
Pressure die-casting, a highly efficient molding process, relies on crucible furnaces that consume a significant amount of energy. These furnaces melt metal ingots, which are then pressed into metallic molds under high pressure and speed. The energy consumption of German light-metal foundries is substantial, reaching 4.4 TWh in 2019 according to the German Federal Statistical Office.
The bivalent furnace technology developed by Fraunhofer IPA allows for the seamless switching between electricity and gas during operation. Traditionally, furnaces have been operated using only one energy source, either gas and oil or electricity. The bivalent furnace overcomes this limitation and offers the flexibility to use different energy sources to meet the energy requirements of crucible furnaces in any operating state.
Working with partner organizations, the research team at Fraunhofer IPA has conducted thermal simulations and optimized plant designs to implement the bivalent furnace technology. The successful testing and commissioning of a bivalent crucible furnace at Bark Magnesium GmbH’s die-casting foundry demonstrate its feasibility. The furnace, integrated into the production process, allows uninterrupted operation while adapting to the fluctuating electricity prices.
The main objective of the research is to utilize energy flexibly, taking advantage of favorable electricity prices without interrupting production. For instance, when electricity prices are high, the furnace can switch to gas operation, and when prices are low, it can switch to electricity operation. The ability to manually or automatically switch between energy sources provides greater control over energy consumption and cost efficiency.
The researchers emphasize the potential of energy-flexible demand in contributing to a renewable energy-oriented electricity system. Industrial companies account for a significant portion of total electricity consumption, making their flexible energy usage crucial for transitioning to renewable energy sources.
In addition to the current development, the Fraunhofer IPA has submitted an application for the follow-up project SynErgie III, aiming to optimize the furnace further, including its heating and network design. Parameters such as temperature distribution in the furnace are being measured to assess energy efficiency. The researchers are also exploring the feasibility of operating the furnace with hydrogen.
Overall, the bivalent furnace technology developed by Fraunhofer IPA and its partners offers a promising solution to reduce energy consumption and production costs in the casting industry. By utilizing the most cost-efficient energy sources and adapting to fluctuating electricity prices, companies can achieve greater energy flexibility and contribute to a more sustainable energy system.